Journal of Geology & Geophysics
Open Access

Geological contribution to the Fongo Tongo bauxite formations (West-Cameroon)

International Conference on Geology

June 22-23, 2015 Florida, USA

Nguimatsia Dongmo Franck Wilfried and Yongue Fouateu Rosea

Posters-Accepted Abstracts: J Geol Geosci

Abstract :

Fongo-Tongo found in the western region of Cameroon, is the second bauxite potential in this country. The present geological study of these bauxite deposits is aimed to identify these materials, and determine their morphological, mineralogical and geochemical features. Fongo-Tongo is topographically a high lands made up of plateau (>1645 mm) on which cuirasses are developed in form of massive flagstones and blocks. Those cuirasses are vesicular, alveolar, conglomeratic, and enclose nodules. The color is variable: red, reddish to reddish-brown, brown, pink, yellowish or ocher. Some cuirasses enclose violet stain and texture, while others are mottling greenish. In low land, they are discontinued and form small blocks with a grain size ranging from centimeter to meters. They are massive, red with some vesicles enclosing red unconsolidated materials. Mineralogically, those cuirasses are dominantly made up of gibbsite and goethite. Quartz, anatase, hematite, maghemite and kaolinite are trace. Geochemically, alumina (Al2O3) content ranging from 37.4 to 57.5 wt.% is dominant. Fe2O3 (<29.5 wt.%), TiO2 (<7.5 wt.%) and SiO2 (0.48-3.21 wt.%) contents are low. Those cuirasses enclose significant content for some trace and rare earth elements (Zr: 504-2310 ppm, Nb: 104-350 ppm, Sr: 0.7- 345 ppm, V: 8-667 ppm, Ce: 24.9-239 ppm, La: 2.4-144 ppm, and Nd: 3.1-126 ppm). From the geochemical point of view, cuirass occurring in Kreu, a locality found in the west of Fongo-Tongo has the highest Al2O3 (57.5 wt.%) content, and lowest SiO2 (3.21 wt.%) and Fe2O3 (3.97 wt.%). They enclose low Zr, Nb, Sr, V, Ce, La, and Nd, and crop out in form of flagstones and discontinued blocks. Globally, bauxites with high alumina and low iron content, silica and titanium deplete have been found in Fongo-Tongo. Thus, the low impurities in bauxites from Fongo-Tongo upgrade their metallogenic importance. The exploitation of this deposit will result in significant environmental impacts in the locality.